Multicylinder rotary engine



Jan. 5,1925. 1,568,053

F. A. BULLINGTON MULTICYLINDER ROTARY ENGINE Jan. 5 1926; 1,568,053

F. A. BuLLlNGToN MULTI CYLI NDR ROTARY ENGINE Filed June 9, 19.23 3 Sheets-Sheet 2 Jane 5 I F. A. BULLINGTON MULTICYLINDER ROTARY ENGINE Filed June 9, 1923 3 Sheets-Shes?l 5 Patented Jan. 1926. f

, UNITDSTATES Lseaosa PATENT OFFICE. 7

'FRANK A. BULLINGTON, 0F KANSAS- CITY, IIVEISSOUR',` ASSIGNOR TO BUL'LINGTON MOTORS, F KANSAS CITY, MISSOURI, A COMMON-LAW TRUST CON?. STING OF SOLOMON STODDARD, ERNEST E. HOWARD, AND FRANK A. BULLINGTON.

i MULTICYLIN DER ROTARY ENGINE.

Application led .Tune 9,

' TON, a citizen of the United States, residing at Kansas City, in the county of Jackson and State of Missouri, have'invented certain new and useful Improvements in Multicylinder Rotary Engines; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable, others skilled in the art to which it appertains to make and use the "same, reference beT 'ing had to the accompanying drawings, and to the letters and figures o f reference marked thereon, which form a part of this specilication. 1.

This invention relatesto alternating pis- 'ton engines in which co-operating': pairs of ipistons Vrotate in anl annular cylinder .or

working chamber about a common axis.

The primary object of the invention is to construct va simple, inexpensive, multi-cylinder engine of the alternating piston type in which means is provided 'for insuring balanced operation and` balanced mechanism, it being an important feature that^the engine may be constructed to provide considerable power and at the same time be confined within a relatively small circumference, thus rendering the engine particularly susceptible for use as an airplane engine although it is not necessarily limited in its application to luse in airplanes. p

In order to render the engine particularly' adaptable for use as an airplane engine, I have provided a hollow, central drive shaft or propeller shaft so that for combat machines, means `will be provided whereby projectiles may be discharged without danger of striking the propeller blades inasmuch as the projectiles can be fired through the longitudinal bore or opening of the hollow drive shaft. In order to render the engine efficient at different altitudes, I have provided means whereby the compression ratio may. be varied; that is, means is provided whereby at low altitudes a smaller charged will be compressed than at higher altitudes. There* fore, the engine is adapted .to be controlled ,so that the compression pressure at higher altitudes will be .equivalent to that at lower altitudes, due to theA fact that increased volume is compressed at higher altitudes t0.

vcompensate for the rariiied atmosphere.

1923. Serial No. 644,368. p

There are'othe'r novel features of my invention, all of which will be referred to hereinafter, reference being had to the accompanying drawings, in which Fig. 1 is a vertical, longitudinal, sectional view through an engine constructed in accordance with my invention.

Fig. 2 is a sectional view on the line 2-'2 of `F1g. l.

Fig. 3 is a sectional view on the line 3 3 of Fig. 5 and Fig. 2.

Fig. 4 is a detailperspective view of the crank carrier.

Fig. 5 is a sectional view on the lipe 5 5 Of F il..

Fig. 6 is a diagrammatic view of the pistons and co-operating parts when the mech*` anism is .fin the position indicated in Fig. 5,

' and Fig. 7 isf a diagrammatic view of the mechanism on the line 7-7 of Fig. i..

The engine is shown as comprising a single unit constructed' of two complementary power translating means co-operating to translate fuel into kinetic energy; the two`z power vtranslating .mechanisms delivering power to'-y a single drive shaft and so balanced within themselves and with relation to one another that balanced operation of the entire unitary structure will be insured.

The unit is' shown as comprising two duplicate unit `members generically designated A and B, the two members communieating energy to the drive shaft C. Since each unit member is a duplicate of the other, I willl vdescribe but one of them, it being understood that except where hereinafter noted, the construction of the member B is substantially identical with the construction of the unit member A.

lar

The ,two members A and B ,are inispaced The two rotors 16 and 17 are provided with hollow shafts 18 and'19, which extend through the hub 15, the hollow shafts being sleeved one upon the other, as clearly shown in Fig. 1.

The shaft 18 has bearings to receive the centrally located hollow drive shaft C, which projects through the casing 11, through the crank case and through the casing 11 for the unit member B. On the front end of the drive shaft C may be secured a propeller 2O and at the opposite end of the shaft C may be provided a thrust. bearing 21.

. The rotors are provided with alternating pistons in any well known manner, it being understood that as is usual in alternating piston engines, there ai'e two pistons on each rotor.

The casing 11' carries a hub 22 which extends into the crank case 10 and on each hub 15 and 22 is keyed a helical gear, the gears being designated 23 and 24 to receive complementary gears on crank shafts of the respective unit members A and B, as will be explained hereinafter. a

The shaft 18 carries a crank arm 25, and the shaft 19 carries a crank arm 26. The two crank arms are connected to the crank shafts 27 and 28 by connecting rods 29 and 30.

The crank shafts are carried by a crank carrier, best shown in Fig. 4. The crank carrier consists of a fiaine 31 having bearing collars 32 and 33 at its respective ends surrounding openings of approximately the diameters of the hubs 15 and 22. lThe collars 32 and33 rest on the hubs -15 and 22 which constitute a supporting bearing for the frame 31,.

The frame is provided with dianietrically oppositely located set-s ofbearings, there being bearings 34, 35, aiid 36 for one crank shaft, for example, 28, and bearings 37, 38, and 39 for the opposite crankshaft, for

example, crank shaft 27. The bearings are offset with respect to the frame proper;

that is, they yextend beyond the main portion of theframe and are connected thereto by webs. The central web 40 has an opening somewhat smaller than the ends of the frame to perlnitthe flange 41 on the drive shaft C tobel fastened thereto so that `theI rotation of the crank carrier will imvpart a rotation to the drive sha-ft, and it 1s through the crank carrier that the drive shaft receives its power.

The crank shaft 27 extends through the 'respective bearings 34, 35, and 36, and the crank shaft 28 extends through the bearings 37, 38, and 39. The crank shaft 27 carries two helical gears 42 and 43 which mesh with the helical gears 23 and 24 on the hubs 15 and 22 and the crank shaft 28,l carries helical gears 44 and 45'which mesh with the helical gears 23 and 24 on the hubs 15 and 22, as will be clearly seen by reference to Fig. 1. It will be noted that the teeth of the gears 43 and 45 are pitched in different directions than the teeth for the gears 42 and 44 so that the thrusts on the crank shafts 27 and 28 will be balanced.

The crank shafts 27 and 28 are really duplicate crank shafts in that they constitute the crank shafts for both unit members A and B and by reference to Fig. 1 it will be noted that so much of the crank shafts 27 and 28 as relate to the mechanism of the unit member A are single pin. single throw and likewise.v so much of the shafts 27 and 28 as relate to unit member B are single pin, single throw crank shafts although the cranks on leach crank shaft rclating to the respective unittmembers are at 18() degrees apart so that the two unit members A and B will tend to balance one another, and in order to balance the structures further, I prefer to counterbalance the crank arms 46 and 47 on the A member side of the unit and correspondingly counterba'lance the cranks on the B member side of the unit. The piston arms fastened to the respective rotors are correspondingly balanced and since the frame 31 rotates about the axis of the motor, with all parts balanced and end thrusts balanced by the gears 42, 43, 44 and 45, it will be apparent that there will be balanced operation of the unit. The endwise thrust genera-ted by the propeller will be taken up by the thrust bearing 21.

The diagram Fig. 6 shows the position of the cranks for the unit member A on dead center position with two cooperating pistons in. position to compress the fucl chargeat about the nioinentof explosion and Fig. 7 shows the'position of the cranks and appurtenances for the unit member ll at the same time. Vhen the pistons in unit B 'are in the same position that the pistons are shown in Fig. 6, then the pistons and their appurtenances in unit member A will be in the position shown in diagram rig; 7.

The crank carrier 31 rotates about the various elements very closely resemble con' structions in sonie'of my prior applications. One essential difference with thc pistons and linkage connections, however, in the present application is that crank shafts for the respective unit members A and B are connected together. In actual practice I=prefer to use only two crank shafts for both unit members because by connecting the cranks for the respective members so that they willv work/as onecrank shaft, certain advantages are obtained in that the parts are-more equally balanced and this is a very important vfeature in connection with airplane engines.

The twomembers, A and B, of the unitv are so .arranged that there Will be an explosion in each memberlialf way between two explosions ofits complementary meinber.l This is accomplished by reason of the fact that the connecting rods of one unit member are in advance of the crankshaft of that member, whereas thev lconnecting rods of the other unit member follow the crank shaft. This is desirable in an arrangement having crank shafts wherein the cr-ank pins are 180 degrees apart. Otherwise, the-explosions in the cylinders of the two members would occur simultaneously, and obviously the alternating explosions are preferable to simultaneous explosions. As

shown, the structure can be' made lighter inunicate through a, plurality of outlet ports 51,52, andfv, having valves 54, 55, and 56 therein. The valves are connected to a bar or actuating member 57 which may be controlled by any suitable means. i The valvesI :ire shown as Lturning-plug valves having `progressively decreasing effectiye port areas from the inlet to the cylinder, `toward the lfinalcompression en-d of the compression Vchamber so that the ports-[51 to .53 can be progressively closed in inverse order; that is, port 53 will be closed before port 52 and 'port 52 will be closed before port 51 by ac- 1tuating the bar 57. The space designated 58 is the compression chamber.l v

vlf no means were provided to relieve the pressure inftlie compression chamber 58 at v low altitudes, the heat generated by the compression of the fuel takeninto the compression chamber 58 would be so great that the" charge would be exploded before full comiii-ession took place, due .to the high compression ratio, so at low altitudes, the valves 56,

' 'and 54 would be open so the fuel which entered the. combustion chamber lwould be partially exhaustedthrough theports 51, 52, and 53, the compression beginning after the piston passed `port 53. The compression n ratio then would be about 5 to 1. At higher altitudes the valve 56 may be closed. and

valve 55 and valve 54 would be open. Therefore, the compression would not begin until the piston passed the port 52. The compression ratio would be greater then than 5 to 1, say 7 to 1. At very high altitudes, the4 valves 54, 55, and 56 would be closed so that ilie compression would start as soon as the compressing piston closed-'ofil the intake port 4-9, when the compression ratio might be as high as 10 tol. These figures are merely given by way ofexample. l

The fuel passed through the ports 51, 52,

and 53 will merely be by-passed around the compressing piston and vre-enter the compression chamber 58 through the port 49, in advance of the following piston, as will be clearly seen by reference to Fig. 2.

Any means canbe provided for operating the bar 57 and, indeed, the valves can be op: erated by any suitable mechanism, it being understood that they are'merely illustrative of a principle which is involved in this type of engine.

It will be seen, therefore, that the compression ratio may be readily varied for. various altitudes, thus rendering the` engine capable of eiicient performance atk either high or l'ow altitudes. The im ortance of this will be readily appreciated y those conversant with aviationl engine requirements.

It'will be apparent from the foregoing that the engine is capable of being easily as- Lembled or disassembled for-inspection or repairs., that the parts are well balanced, thatthe operating performance will be a liiglily'balanced one, insuring smooth run-.-

ning performance, and that the engine is flexible'in its performance to adapt itself for nog usent varying altitudes in a most convenient manner and one of the important features of the invention aside from the eliicieiit op-- `eration Vis the construction by means vof which the drive shaft can be constructed hollow to permit use of the 'engine in a combat f machine so that the projectiles from agun.

can be passed through the center of the A shaft, thus eliminating the necessity of tim-l ing devices to eliminate vchances of.striking the propeller.

Y vIt is also an important feature of my invention that the engine may be so constructed .that the exploded gases ,are expanded to a greater degreeor over a longer effective period than under standard practice. For example, safe limits of compression ratio foi'- internal combustion engines is about five to one', and the expansion is-about the saine, the result being that theburnt gases are exhausted to atmosphere while they are still capable of doing useful work. But in my invention, the burnt gases areexpand'ed'in the engine during almost complete expansion so that the full value of the expandingV gases may be y therein, the piston means dividing the cylinder into a compression chamber and an expansion chamber of equal volumetric capacity, and means for maintaining the density of the contents of the compression chamberV constantV by varying the initial compression volume at diHerent altitudes.

3. An internal combustion engine comprising two rotary unit members, a unit -.crank shaftdriving mechanism interconnecting the two unit members into a single unitary structure', the crank shaft mechanism including oppositely located crank shafts parallel with `the axis of'the engine, and means for balancing end thrusts of the vcrank shafts. l I

4. An internal combustion engine comprising two rotary unit members, a unit crank shaft driving mechanism interconnecting the two unit members'into a single vunitary structure? the crank shaft drivmg mechanism' including crank shafts parallel with the axis of the engine, a single crank pin en each crankshaft for each unit, the crank pins being disposed at angles of 180 degrees apart, and means vfor balancing the end thrusts of the crank shafts. Y

An internal combustion engine comprising two rotary unit.A members, a unit crank shaft driving mechanism interconnecting the Vtwo unit members into a single unitary structure, the crank shaft mechanism including a crank carrier, va driveshaft receiving its motion from the crank shaft the unit members to the crank shaft carrier...

carrier, cranks carried by the crank sha'ft carrier, and means connecting the cranks to.

pistons .v in the unit members whereby m'otlon maybe delivered from the pistons in y6. In an internal combustion engine, two rotary unitmembershaving alternating pistons therein, crank shaft mechanisms for interconnecting thealternating pistons in the respective unit members, and -means for alternately exploding charges in' one of the unit members Imidway between the explosion in the complementary `unit member. F

7. An internal combustion engine comprising two rotary unit members and a ro-A tary unit crank shaft driving mechanism having planetary movement about a common axis, interconnecting the two unit members into a single unitary structure, the crank shaft mechanism including balanced crank shafts, the crank pins for each unit member being set at an angle of 180 with respect to the crank pins of its complementary unit member.

8. An internal combustion engine com'-4 prising two rotary unit members and a rotary unit crank shaft driving mechanism having planetary movement about a common axis, inter-connecting the two unit members into a' single unitary structure, the crank shaft mechanism including balanced crank shafts, vthe crankpins for each unit member being setat an angle of 180 with respect to the crank pins of its complementary unit member, fixed gears concentric with'the axes of the unit members, and geared .connections between the crank vshafts andthe fixed gears. v

9. An internal combustion engine com-- prising two rotary unit members and a rotary unit crank shaft driving mechanism having planetary movement about a com-k 10. An lnternall combustionlengin'e comprising two, rotary unit members and a rotary unit crank shaft drivino' mechanism having planetary 'movement about a common axls, inter-'connecting the two unit members into a single unitary structure, the

crank shaft mechanism including diametrically oppositely located balanced crank shafts, the crank pins for each vunit member being setat an angle of 180 Awithrespect to the crank pins of.' its complementary unit member. i

l11. An internal combustion engine comprising two rotary unit members, each including a cylinder and rotary pistons therein', a rotary unit crank shaft driving mechanism having planetaryvmovement about a common axis, inter-connecting the two unit embers into a single unitary structure, the

crank shaft'mechanism including independ-- ent sets of cranks, one set foreach unit member, diametrically oppositely located balanced crank shafts; each crank shaft carrying one crank of each set, one cran'kon each shaft being at an angle of 180 with respect to the other crank on the samev shaft, and crank connections between the vrespective cranks and the. pistons, the crank connections of one unit memberat all times being in advance of the crank connections of the other unit member.

12. An internal combustion engine com? prising two rotary unit members, each including a cylinder and rotary pistons therein, a rotary unit crank shaft driving mechanism havin` planetary movement about a common axis, inter-connecting the two unit members into a single unitary structure, the crank shaft mechanism including independent sets of cranks, one set for each unit member, diametrically oppositely located balanced crank shafts, each crank shaft carrying onecrank of each set, one crank on eachl 15 tions of one unit member at )all times being" 20 in advance of the crank connections of the other unit member, the advanced crank connections for one unit being at all times in advance of the crank shafts, the following crank connections for the other unit at all 25 times following' the crank shafts.

In testimony whereof aiiiX my signature.

FRANK A. BULLINGTON. 

